So I waited and waited this evening and finally the clouds blew away. It was going on 10pm by then, and temps had dropped down into the 30's (will be
in the upper 20s later), blowing wind, very cold, can't find my heavy coat.

Went out there anyway to try my new mount out. Start a polar alignment and realized that my reticle isn't illuminated....so I pulled my pen light out
and attempted to cast just a little light at the end of the polar scope...ow......I'm blind! hehehehe.

I get Polaris lined up......have to be good enough as it's cold and I'm cold with only a light jacket, so I lined the camera up with Orion and took
several shots at 2 minutes.....don't have the lap top hooked up, this was a rush job. Got done, went inside and pulled the images from the SD card and
saw this:

So I'm dropping the "F" bomb......stupid auto focus camera, I'd bumped the lens so it wasn't on the mark and didn't know it......

But then I realized something: this was a 2 minute exposure....no star trails! Yay! I got the new mount aligned correctly.

So I dithered and decided to go back out again double checking the lens focus this time. Unfortunately, Orion is getting closer and closer to the
western horizon and the huge and bright moon is rising in the east. I captured this:

In focus this time (no, tree isn't because the camera is moving with the sky). 55mm, f5.6 (stuck with that for now. I need to see if Magic Lantern can
override it), ISO 400, at 120 second exposure.

So, looking into overriding my f stop on my lens with Magic Lantern seems to be no good. I can access it with the program, but it won't let me
decrease it, only increase it.

My 18mm to 55mm lens changes the f stop automatically. The lowest I can have the f stop is at 3.5 at 18mm. If I zoom in to 55mm, it increases the f
stop to 5.6, and I can not take it below that, I can increase it however.

This of course sucks since trying to replicate what you were able to do
here, I need to back the f stop down to 2.3, which is lower than the lens can go even at 18mm.

This of course is quite frustrating since my goal is to let more light in. In order to do the same as you did, but at f stop 5.6, I would have to
increase the exposure time from 2 minutes to 6 minutes! Ouch. Not sure if I had the mount polar aligned that well for shots that long, but also
wondering how saturated the CCD sensor would be for that long of a exposure.

Oh, and for any who'd like to play with it, I found a interesting online calculator for this here:

My 18mm to 55mm lens changes the f stop automatically. The lowest I can have the f stop is at 3.5 at 18mm. If I zoom in to 55mm, it increases the f
stop to 5.6, and I can not take it below that, I can increase it however. This of course sucks since trying to replicate what you were able to do
here, I need to back the f stop down to 2.3, which is lower than the lens can go even at 18mm.

Indeed, diaphragm is linked to the construction of the lens.
Remember that shot was only a stack of 5 images. This shot however was a stack of 45 at f/5.6 and still managed to get
some good details.
At 55mm with good PA you should go easy to 3 - 4 minutes. Obviously you will saturate the sensor more with longer shutterspeeds. Saturation is also
directly connected with heat/time(sensor), so when it's cold outside saturation will happen slower as it will help to cool down the sensor.
A good thing to do is shutting down the camera for 5-10 min after 30-40 min of taking shots. This will help you a lot to lower the noise level in your
images.
Another thing to do is taking dark images and use them is the stacking process, be sure to take them at the same time and settings as you light
images.

In your case I would first try to get 3 minutes and see how the image turns out.
Settings: 3min, f5.6, iso800/1000

It's better to get a little bit overexposed than underexposed. This can be corrected in post and will result in less noise than an underexposed image.
Shoot in raw also and try to take as much images possible.

I'm preparing to go out in short time hoping it will stay clear tonight

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